An evaporator fan for cooling and dehumidification. One application, but not limited to, a device commonly referred to as a swamp cooler is essentially a large box-like frame containing a large fan. The fan is enclosed by one or more water-wetted pads usually made of excelsior or cellulose. In use, the fan draws in hot outside air through the wetted pads (which are continually soaked by water from a pump), cooling the air as the air evaporates water molecules from the water-wetted pads. The fan blows the water-cooled air into the house or building that is being cooled and then out a deliberate vent.
It is often called a swamp cooler because on high humidity days cooling is diminished due to lack of evaporation in the pads making the area feel muggy similar to a swamp. On dry days, a standard swamp cooler works fine. In an area, such as Arizona, where the high humidity monsoon air occurs for short periods the cooling and dehumidifying affects of this evaporator would enhance capabilities.
The typical swamp cooler (aka evaporative cooler) operates with a low horsepower motor which pumps water from the floor, or tank, of the cooler to the top of the cooler and over the pads. The water level in the tank is kept constant with a float valve that opens when water is needed to keep the tank full due to loss of evaporation.
When the pumped water reaches the top of the cooler pads it proceeds to trickle down the face of the cooler pads being drawn through and evaporated off. A second motor drives the fan which draws air from the outside through the pads, then pushes the cooled air into the desired area. Significant cooling effect is produced when the water evaporates as air passes through the pads. The cooling is produced by evaporation converting liquid water to vapor. As stated above, the problem with swamp coolers are that they do not work well during humid periods. Several attempts have been made to solve this problem.
U.S. Pat. No. 5,383,337 to Baker describes an apparatus for pre-cooling water supplied to a “swamp cooler”. What is needed is a device that allows a swamp cooler to be used in humid conditions but absolves the necessity of pre-cooling the water separately and prior to use by the swamp cooler. The present invention meets this need.